The invention: The first industrial robots, Unimates were designed to replace humans in undesirable, hazardous, and monotonous jobs.
The people behind the invention:
Karel Capek (1890-1938), a Czech playwright
George C. Devol, Jr. (1912- ), an American inventor
Joseph F. Engelberger (1925- ), an American entrepreneur
Robots, from Concept to Reality
The 1920 play Rossum’s Universal Robots, by Czech writer Karel Capek, introduced robots to the world. Capek’s humanoid robots— robot, a word created by Capek, essentially means slave—revolted and took over the world, which made the concept of robots somewhat frightening. The development of robots, which are now defined as machines that do work that would ordinarily be carried out by humans, has not yet advanced to the stage of being able to produce humanoid robots, however, much less robots capable of carrying out a revolt.
Most modern robots are found in industry, where they perform dangerous or monotonous tasks that previously were done by humans. The first industrial robots were the Unimates (short for “universal automaton”), which were derived from a robot design invented by George C. Devol and patented in 1954. The first Unimate prototypes, developed by Devol and Joseph F. Engelberger, were completed in 1962 by Unimation Incorporated and tested in industry. They were so successful that the company, located in Danbury, Connecticut, manufactured and sold thousands of Unimates to companies in the United States and abroad. Unimates are very versatile at performing routine industrial tasks and are easy to program and reprogram. The tasks they perform include various steps in automobile manufacturing, spray painting, and running lathes. The huge success of the Unimates led companies in other countries to produce their own industrial robots, and advancing technology has improved all industrial robots tremendously.
A New Industrial Revolution
Each of the first Unimate robots, which were priced at $25,000, was almost five feet tall and stood on a four-foot by five-foot base. It has often been said that a Unimate resembles the gun turret of a minitank, set atop a rectangular box. In operation, such a robot will swivel, swing, and/or dip and turn at the wrist of its hydraulically powered arm, which has a steel hand. The precisely articulated hand can pick up an egg without breaking it. At the same time, however, it is powerful enough to lift a hundred-pound weight.
The Unimate is a robotic jack of all trades: It can be programmed, in about an hour, to carry out a complex operation, after which it can have its memory erased and be reprogrammed in another hour to do something entirely different. In addition, programming a Unimate requires no special training. The programmer simply uses a teach-cable selector that allows the programmer to move the Unimate arm through the desired operation. This selector consists of a group of pushbutton control boxes, each of which is equipped with buttons in opposed pairs. Each button pair records the motion that will put a Unimate arm through one of five possible motions, in opposite directions. For example, pushing the correct buttons will record a motion in which the robot’s arm moves out to one side, aims upward, and angles appropriately to carry out the first portion of its intended job. If the Unimate overshoots, undershoots, or otherwise performs the function incorrectly, the activity can be fine-tuned with the buttons.
Once the desired action has been performed correctly, pressing a “record” button on the robot’s main control panel enters the operation into its computer memory. In this fashion, Unimates can be programmed to carry out complex actions that require as many as two hundred commands. Each command tells the Unimate to move its arm or hand in a given way by combining the following five motions: sliding the arm forward, swinging the arm horizontally, tilting the arm up or down, bending the wrist up or down, and swivel-ing the hand in a half-circle clockwise or counterclockwise.
Before pressing the “record” button on the Unimate’s control panel, the operator can also command the hand to grasp an item when in a particular position. Furthermore, the strength of the
grasp can be controlled, as can the duration of time between each action. Finally, the Unimate can be instructed to start or stop another routine (such as operating a paint sprayer) at any point. Once the instructor is satisfied with the robot’s performance, pressing a “repeat continuous” control starts the Unimate working. The robot will stop repeating its program only when it is turned off.
Inside the base of an original Unimate is a magnetic drum that contains its memory. The drum turns intermittently, moving each of two hundred long strips of metal beneath recording heads. This strip movement brings specific portions of each strip—dictated by particular motions—into position below the heads. When the “record” button is pressed after a motion is completed, the hand position is recorded as a series of numbers that tells the computer the complete hand position in each of the five permissible movement modes.
Once “repeat continuous” is pressed, the computer begins the command series by turning the drum appropriately, carrying out each memorized command in the chosen sequence. When the sequence ends, the computer begins again, and the process repeats until the robot is turned off. If a Unimate user wishes to change the function of such a robot, its drum can be erased and reprogrammed. Users can also remove programmed drums, store them for future use, and replace them with new drums.
Consequences
The first Unimates had a huge impact on industrial manufacturing. In time, different sizes of robots became available so that additional tasks could be performed, and the robots’ circuitry was improved. Because they have no eyes and cannot make judgments, Unimates are limited to relatively simple tasks that are coordinated by means of timed operations and simple computer interactions.
Most of the thousands of modern Unimates and their multinational cousins in industry are very similar to the original Unimates in terms of general capabilities, although they can now assemble watches and perform other delicate tasks that the original Unimates could not perform. The crude magnetic drums and computer controls have given way to silicon chips and microcomputers, which have made the robots more accurate and reliable. Some robots can even build other robots, and others can perform tasks such as mowing lawns and walking dogs.
Various improvements have been planned that will ultimately lead to some very interesting and advanced modifications. It is likely that highly sophisticated humanoid robots like those predicted by Karel Capek will be produced at some future time. One can only hope that these robots will not rebel against their human creators.
See also CAD/CAM; Robot (household); SAINT; Virtual machine.
